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Diffstat (limited to 'thirdparty/bullet/BulletSoftBody/btDeformableMultiBodyDynamicsWorld.cpp')
| -rw-r--r-- | thirdparty/bullet/BulletSoftBody/btDeformableMultiBodyDynamicsWorld.cpp | 814 |
1 files changed, 0 insertions, 814 deletions
diff --git a/thirdparty/bullet/BulletSoftBody/btDeformableMultiBodyDynamicsWorld.cpp b/thirdparty/bullet/BulletSoftBody/btDeformableMultiBodyDynamicsWorld.cpp deleted file mode 100644 index 983e622b5f..0000000000 --- a/thirdparty/bullet/BulletSoftBody/btDeformableMultiBodyDynamicsWorld.cpp +++ /dev/null @@ -1,814 +0,0 @@ -/* - Written by Xuchen Han <xuchenhan2015@u.northwestern.edu> - - Bullet Continuous Collision Detection and Physics Library - Copyright (c) 2019 Google Inc. http://bulletphysics.org - This software is provided 'as-is', without any express or implied warranty. - In no event will the authors be held liable for any damages arising from the use of this software. - Permission is granted to anyone to use this software for any purpose, - including commercial applications, and to alter it and redistribute it freely, - subject to the following restrictions: - 1. The origin of this software must not be misrepresented; you must not claim that you wrote the original software. If you use this software in a product, an acknowledgment in the product documentation would be appreciated but is not required. - 2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software. - 3. This notice may not be removed or altered from any source distribution. - */ - -/* ====== Overview of the Deformable Algorithm ====== */ - -/* -A single step of the deformable body simulation contains the following main components: -Call internalStepSimulation multiple times, to achieve 240Hz (4 steps of 60Hz). -1. Deformable maintaintenance of rest lengths and volume preservation. Forces only depend on position: Update velocity to a temporary state v_{n+1}^* = v_n + explicit_force * dt / mass, where explicit forces include gravity and elastic forces. -2. Detect discrete collisions between rigid and deformable bodies at position x_{n+1}^* = x_n + dt * v_{n+1}^*. - -3a. Solve all constraints, including LCP. Contact, position correction due to numerical drift, friction, and anchors for deformable. - -3b. 5 Newton steps (multiple step). Conjugent Gradient solves linear system. Deformable Damping: Then velocities of deformable bodies v_{n+1} are solved in - M(v_{n+1} - v_{n+1}^*) = damping_force * dt / mass, - by a conjugate gradient solver, where the damping force is implicit and depends on v_{n+1}. - Make sure contact constraints are not violated in step b by performing velocity projections as in the paper by Baraff and Witkin https://www.cs.cmu.edu/~baraff/papers/sig98.pdf. Dynamic frictions are treated as a force and added to the rhs of the CG solve, whereas static frictions are treated as constraints similar to contact. -4. Position is updated via x_{n+1} = x_n + dt * v_{n+1}. - - -The algorithm also closely resembles the one in http://physbam.stanford.edu/~fedkiw/papers/stanford2008-03.pdf - */ - -#include <stdio.h> -#include "btDeformableMultiBodyDynamicsWorld.h" -#include "DeformableBodyInplaceSolverIslandCallback.h" -#include "btDeformableBodySolver.h" -#include "LinearMath/btQuickprof.h" -#include "btSoftBodyInternals.h" -btDeformableMultiBodyDynamicsWorld::btDeformableMultiBodyDynamicsWorld(btDispatcher* dispatcher, btBroadphaseInterface* pairCache, btDeformableMultiBodyConstraintSolver* constraintSolver, btCollisionConfiguration* collisionConfiguration, btDeformableBodySolver* deformableBodySolver) - : btMultiBodyDynamicsWorld(dispatcher, pairCache, (btMultiBodyConstraintSolver*)constraintSolver, collisionConfiguration), - m_deformableBodySolver(deformableBodySolver), - m_solverCallback(0) -{ - m_drawFlags = fDrawFlags::Std; - m_drawNodeTree = true; - m_drawFaceTree = false; - m_drawClusterTree = false; - m_sbi.m_broadphase = pairCache; - m_sbi.m_dispatcher = dispatcher; - m_sbi.m_sparsesdf.Initialize(); - m_sbi.m_sparsesdf.setDefaultVoxelsz(0.005); - m_sbi.m_sparsesdf.Reset(); - - m_sbi.air_density = (btScalar)1.2; - m_sbi.water_density = 0; - m_sbi.water_offset = 0; - m_sbi.water_normal = btVector3(0, 0, 0); - m_sbi.m_gravity.setValue(0, -9.8, 0); - m_internalTime = 0.0; - m_implicit = false; - m_lineSearch = false; - m_useProjection = false; - m_ccdIterations = 5; - m_solverDeformableBodyIslandCallback = new DeformableBodyInplaceSolverIslandCallback(constraintSolver, dispatcher); -} - -btDeformableMultiBodyDynamicsWorld::~btDeformableMultiBodyDynamicsWorld() -{ - delete m_solverDeformableBodyIslandCallback; -} - -void btDeformableMultiBodyDynamicsWorld::internalSingleStepSimulation(btScalar timeStep) -{ - BT_PROFILE("internalSingleStepSimulation"); - if (0 != m_internalPreTickCallback) - { - (*m_internalPreTickCallback)(this, timeStep); - } - reinitialize(timeStep); - - // add gravity to velocity of rigid and multi bodys - applyRigidBodyGravity(timeStep); - - ///apply gravity and explicit force to velocity, predict motion - predictUnconstraintMotion(timeStep); - - ///perform collision detection that involves rigid/multi bodies - btMultiBodyDynamicsWorld::performDiscreteCollisionDetection(); - - btMultiBodyDynamicsWorld::calculateSimulationIslands(); - - beforeSolverCallbacks(timeStep); - - ///solve contact constraints and then deformable bodies momemtum equation - solveConstraints(timeStep); - - afterSolverCallbacks(timeStep); - - performDeformableCollisionDetection(); - - applyRepulsionForce(timeStep); - - performGeometricCollisions(timeStep); - - integrateTransforms(timeStep); - - ///update vehicle simulation - btMultiBodyDynamicsWorld::updateActions(timeStep); - - updateActivationState(timeStep); - // End solver-wise simulation step - // /////////////////////////////// -} - -void btDeformableMultiBodyDynamicsWorld::performDeformableCollisionDetection() -{ - for (int i = 0; i < m_softBodies.size(); ++i) - { - m_softBodies[i]->m_softSoftCollision = true; - } - - for (int i = 0; i < m_softBodies.size(); ++i) - { - for (int j = i; j < m_softBodies.size(); ++j) - { - m_softBodies[i]->defaultCollisionHandler(m_softBodies[j]); - } - } - - for (int i = 0; i < m_softBodies.size(); ++i) - { - m_softBodies[i]->m_softSoftCollision = false; - } -} - -void btDeformableMultiBodyDynamicsWorld::updateActivationState(btScalar timeStep) -{ - for (int i = 0; i < m_softBodies.size(); i++) - { - btSoftBody* psb = m_softBodies[i]; - psb->updateDeactivation(timeStep); - if (psb->wantsSleeping()) - { - if (psb->getActivationState() == ACTIVE_TAG) - psb->setActivationState(WANTS_DEACTIVATION); - if (psb->getActivationState() == ISLAND_SLEEPING) - { - psb->setZeroVelocity(); - } - } - else - { - if (psb->getActivationState() != DISABLE_DEACTIVATION) - psb->setActivationState(ACTIVE_TAG); - } - } - btMultiBodyDynamicsWorld::updateActivationState(timeStep); -} - -void btDeformableMultiBodyDynamicsWorld::applyRepulsionForce(btScalar timeStep) -{ - BT_PROFILE("btDeformableMultiBodyDynamicsWorld::applyRepulsionForce"); - for (int i = 0; i < m_softBodies.size(); i++) - { - btSoftBody* psb = m_softBodies[i]; - if (psb->isActive()) - { - psb->applyRepulsionForce(timeStep, true); - } - } -} - -void btDeformableMultiBodyDynamicsWorld::performGeometricCollisions(btScalar timeStep) -{ - BT_PROFILE("btDeformableMultiBodyDynamicsWorld::performGeometricCollisions"); - // refit the BVH tree for CCD - for (int i = 0; i < m_softBodies.size(); ++i) - { - btSoftBody* psb = m_softBodies[i]; - if (psb->isActive()) - { - m_softBodies[i]->updateFaceTree(true, false); - m_softBodies[i]->updateNodeTree(true, false); - for (int j = 0; j < m_softBodies[i]->m_faces.size(); ++j) - { - btSoftBody::Face& f = m_softBodies[i]->m_faces[j]; - f.m_n0 = (f.m_n[1]->m_x - f.m_n[0]->m_x).cross(f.m_n[2]->m_x - f.m_n[0]->m_x); - } - } - } - - // clear contact points & update DBVT - for (int r = 0; r < m_ccdIterations; ++r) - { - for (int i = 0; i < m_softBodies.size(); ++i) - { - btSoftBody* psb = m_softBodies[i]; - if (psb->isActive()) - { - // clear contact points in the previous iteration - psb->m_faceNodeContacts.clear(); - - // update m_q and normals for CCD calculation - for (int j = 0; j < psb->m_nodes.size(); ++j) - { - psb->m_nodes[j].m_q = psb->m_nodes[j].m_x + timeStep * psb->m_nodes[j].m_v; - } - for (int j = 0; j < psb->m_faces.size(); ++j) - { - btSoftBody::Face& f = psb->m_faces[j]; - f.m_n1 = (f.m_n[1]->m_q - f.m_n[0]->m_q).cross(f.m_n[2]->m_q - f.m_n[0]->m_q); - f.m_vn = (f.m_n[1]->m_v - f.m_n[0]->m_v).cross(f.m_n[2]->m_v - f.m_n[0]->m_v) * timeStep * timeStep; - } - } - } - - // apply CCD to register new contact points - for (int i = 0; i < m_softBodies.size(); ++i) - { - for (int j = i; j < m_softBodies.size(); ++j) - { - btSoftBody* psb1 = m_softBodies[i]; - btSoftBody* psb2 = m_softBodies[j]; - if (psb1->isActive() && psb2->isActive()) - { - m_softBodies[i]->geometricCollisionHandler(m_softBodies[j]); - } - } - } - - int penetration_count = 0; - for (int i = 0; i < m_softBodies.size(); ++i) - { - btSoftBody* psb = m_softBodies[i]; - if (psb->isActive()) - { - penetration_count += psb->m_faceNodeContacts.size(); - } - } - if (penetration_count == 0) - { - break; - } - - // apply inelastic impulse - for (int i = 0; i < m_softBodies.size(); ++i) - { - btSoftBody* psb = m_softBodies[i]; - if (psb->isActive()) - { - psb->applyRepulsionForce(timeStep, false); - } - } - } -} - -void btDeformableMultiBodyDynamicsWorld::softBodySelfCollision() -{ - BT_PROFILE("btDeformableMultiBodyDynamicsWorld::softBodySelfCollision"); - for (int i = 0; i < m_softBodies.size(); i++) - { - btSoftBody* psb = m_softBodies[i]; - if (psb->isActive()) - { - psb->defaultCollisionHandler(psb); - } - } -} - -void btDeformableMultiBodyDynamicsWorld::positionCorrection(btScalar timeStep) -{ - // correct the position of rigid bodies with temporary velocity generated from split impulse - btContactSolverInfo infoGlobal; - btVector3 zero(0, 0, 0); - for (int i = 0; i < m_nonStaticRigidBodies.size(); ++i) - { - btRigidBody* rb = m_nonStaticRigidBodies[i]; - //correct the position/orientation based on push/turn recovery - btTransform newTransform; - btVector3 pushVelocity = rb->getPushVelocity(); - btVector3 turnVelocity = rb->getTurnVelocity(); - if (pushVelocity[0] != 0.f || pushVelocity[1] != 0 || pushVelocity[2] != 0 || turnVelocity[0] != 0.f || turnVelocity[1] != 0 || turnVelocity[2] != 0) - { - btTransformUtil::integrateTransform(rb->getWorldTransform(), pushVelocity, turnVelocity * infoGlobal.m_splitImpulseTurnErp, timeStep, newTransform); - rb->setWorldTransform(newTransform); - rb->setPushVelocity(zero); - rb->setTurnVelocity(zero); - } - } -} - -void btDeformableMultiBodyDynamicsWorld::integrateTransforms(btScalar timeStep) -{ - BT_PROFILE("integrateTransforms"); - positionCorrection(timeStep); - btMultiBodyDynamicsWorld::integrateTransforms(timeStep); - for (int i = 0; i < m_softBodies.size(); ++i) - { - btSoftBody* psb = m_softBodies[i]; - for (int j = 0; j < psb->m_nodes.size(); ++j) - { - btSoftBody::Node& node = psb->m_nodes[j]; - btScalar maxDisplacement = psb->getWorldInfo()->m_maxDisplacement; - btScalar clampDeltaV = maxDisplacement / timeStep; - for (int c = 0; c < 3; c++) - { - if (node.m_v[c] > clampDeltaV) - { - node.m_v[c] = clampDeltaV; - } - if (node.m_v[c] < -clampDeltaV) - { - node.m_v[c] = -clampDeltaV; - } - } - node.m_x = node.m_x + timeStep * (node.m_v + node.m_splitv); - node.m_q = node.m_x; - node.m_vn = node.m_v; - } - // enforce anchor constraints - for (int j = 0; j < psb->m_deformableAnchors.size(); ++j) - { - btSoftBody::DeformableNodeRigidAnchor& a = psb->m_deformableAnchors[j]; - btSoftBody::Node* n = a.m_node; - n->m_x = a.m_cti.m_colObj->getWorldTransform() * a.m_local; - - // update multibody anchor info - if (a.m_cti.m_colObj->getInternalType() == btCollisionObject::CO_FEATHERSTONE_LINK) - { - btMultiBodyLinkCollider* multibodyLinkCol = (btMultiBodyLinkCollider*)btMultiBodyLinkCollider::upcast(a.m_cti.m_colObj); - if (multibodyLinkCol) - { - btVector3 nrm; - const btCollisionShape* shp = multibodyLinkCol->getCollisionShape(); - const btTransform& wtr = multibodyLinkCol->getWorldTransform(); - psb->m_worldInfo->m_sparsesdf.Evaluate( - wtr.invXform(n->m_x), - shp, - nrm, - 0); - a.m_cti.m_normal = wtr.getBasis() * nrm; - btVector3 normal = a.m_cti.m_normal; - btVector3 t1 = generateUnitOrthogonalVector(normal); - btVector3 t2 = btCross(normal, t1); - btMultiBodyJacobianData jacobianData_normal, jacobianData_t1, jacobianData_t2; - findJacobian(multibodyLinkCol, jacobianData_normal, a.m_node->m_x, normal); - findJacobian(multibodyLinkCol, jacobianData_t1, a.m_node->m_x, t1); - findJacobian(multibodyLinkCol, jacobianData_t2, a.m_node->m_x, t2); - - btScalar* J_n = &jacobianData_normal.m_jacobians[0]; - btScalar* J_t1 = &jacobianData_t1.m_jacobians[0]; - btScalar* J_t2 = &jacobianData_t2.m_jacobians[0]; - - btScalar* u_n = &jacobianData_normal.m_deltaVelocitiesUnitImpulse[0]; - btScalar* u_t1 = &jacobianData_t1.m_deltaVelocitiesUnitImpulse[0]; - btScalar* u_t2 = &jacobianData_t2.m_deltaVelocitiesUnitImpulse[0]; - - btMatrix3x3 rot(normal.getX(), normal.getY(), normal.getZ(), - t1.getX(), t1.getY(), t1.getZ(), - t2.getX(), t2.getY(), t2.getZ()); // world frame to local frame - const int ndof = multibodyLinkCol->m_multiBody->getNumDofs() + 6; - btMatrix3x3 local_impulse_matrix = (Diagonal(n->m_im) + OuterProduct(J_n, J_t1, J_t2, u_n, u_t1, u_t2, ndof)).inverse(); - a.m_c0 = rot.transpose() * local_impulse_matrix * rot; - a.jacobianData_normal = jacobianData_normal; - a.jacobianData_t1 = jacobianData_t1; - a.jacobianData_t2 = jacobianData_t2; - a.t1 = t1; - a.t2 = t2; - } - } - } - psb->interpolateRenderMesh(); - } -} - -void btDeformableMultiBodyDynamicsWorld::solveConstraints(btScalar timeStep) -{ - BT_PROFILE("btDeformableMultiBodyDynamicsWorld::solveConstraints"); - // save v_{n+1}^* velocity after explicit forces - m_deformableBodySolver->backupVelocity(); - - // set up constraints among multibodies and between multibodies and deformable bodies - setupConstraints(); - - // solve contact constraints - solveContactConstraints(); - - // set up the directions in which the velocity does not change in the momentum solve - if (m_useProjection) - m_deformableBodySolver->m_objective->m_projection.setProjection(); - else - m_deformableBodySolver->m_objective->m_projection.setLagrangeMultiplier(); - - // for explicit scheme, m_backupVelocity = v_{n+1}^* - // for implicit scheme, m_backupVelocity = v_n - // Here, set dv = v_{n+1} - v_n for nodes in contact - m_deformableBodySolver->setupDeformableSolve(m_implicit); - - // At this point, dv should be golden for nodes in contact - // proceed to solve deformable momentum equation - m_deformableBodySolver->solveDeformableConstraints(timeStep); -} - -void btDeformableMultiBodyDynamicsWorld::setupConstraints() -{ - // set up constraints between multibody and deformable bodies - m_deformableBodySolver->setConstraints(m_solverInfo); - - // set up constraints among multibodies - { - sortConstraints(); - // setup the solver callback - btMultiBodyConstraint** sortedMultiBodyConstraints = m_sortedMultiBodyConstraints.size() ? &m_sortedMultiBodyConstraints[0] : 0; - btTypedConstraint** constraintsPtr = getNumConstraints() ? &m_sortedConstraints[0] : 0; - m_solverDeformableBodyIslandCallback->setup(&m_solverInfo, constraintsPtr, m_sortedConstraints.size(), sortedMultiBodyConstraints, m_sortedMultiBodyConstraints.size(), getDebugDrawer()); - - // build islands - m_islandManager->buildIslands(getCollisionWorld()->getDispatcher(), getCollisionWorld()); - } -} - -void btDeformableMultiBodyDynamicsWorld::sortConstraints() -{ - m_sortedConstraints.resize(m_constraints.size()); - int i; - for (i = 0; i < getNumConstraints(); i++) - { - m_sortedConstraints[i] = m_constraints[i]; - } - m_sortedConstraints.quickSort(btSortConstraintOnIslandPredicate2()); - - m_sortedMultiBodyConstraints.resize(m_multiBodyConstraints.size()); - for (i = 0; i < m_multiBodyConstraints.size(); i++) - { - m_sortedMultiBodyConstraints[i] = m_multiBodyConstraints[i]; - } - m_sortedMultiBodyConstraints.quickSort(btSortMultiBodyConstraintOnIslandPredicate()); -} - -void btDeformableMultiBodyDynamicsWorld::solveContactConstraints() -{ - // process constraints on each island - m_islandManager->processIslands(getCollisionWorld()->getDispatcher(), getCollisionWorld(), m_solverDeformableBodyIslandCallback); - - // process deferred - m_solverDeformableBodyIslandCallback->processConstraints(); - m_constraintSolver->allSolved(m_solverInfo, m_debugDrawer); - - // write joint feedback - { - for (int i = 0; i < this->m_multiBodies.size(); i++) - { - btMultiBody* bod = m_multiBodies[i]; - - bool isSleeping = false; - - if (bod->getBaseCollider() && bod->getBaseCollider()->getActivationState() == ISLAND_SLEEPING) - { - isSleeping = true; - } - for (int b = 0; b < bod->getNumLinks(); b++) - { - if (bod->getLink(b).m_collider && bod->getLink(b).m_collider->getActivationState() == ISLAND_SLEEPING) - isSleeping = true; - } - - if (!isSleeping) - { - //useless? they get resized in stepVelocities once again (AND DIFFERENTLY) - m_scratch_r.resize(bod->getNumLinks() + 1); //multidof? ("Y"s use it and it is used to store qdd) - m_scratch_v.resize(bod->getNumLinks() + 1); - m_scratch_m.resize(bod->getNumLinks() + 1); - - if (bod->internalNeedsJointFeedback()) - { - if (!bod->isUsingRK4Integration()) - { - if (bod->internalNeedsJointFeedback()) - { - bool isConstraintPass = true; - bod->computeAccelerationsArticulatedBodyAlgorithmMultiDof(m_solverInfo.m_timeStep, m_scratch_r, m_scratch_v, m_scratch_m, isConstraintPass, - getSolverInfo().m_jointFeedbackInWorldSpace, - getSolverInfo().m_jointFeedbackInJointFrame); - } - } - } - } - } - } - - for (int i = 0; i < this->m_multiBodies.size(); i++) - { - btMultiBody* bod = m_multiBodies[i]; - bod->processDeltaVeeMultiDof2(); - } -} - -void btDeformableMultiBodyDynamicsWorld::addSoftBody(btSoftBody* body, int collisionFilterGroup, int collisionFilterMask) -{ - m_softBodies.push_back(body); - - // Set the soft body solver that will deal with this body - // to be the world's solver - body->setSoftBodySolver(m_deformableBodySolver); - - btCollisionWorld::addCollisionObject(body, - collisionFilterGroup, - collisionFilterMask); -} - -void btDeformableMultiBodyDynamicsWorld::predictUnconstraintMotion(btScalar timeStep) -{ - BT_PROFILE("predictUnconstraintMotion"); - btMultiBodyDynamicsWorld::predictUnconstraintMotion(timeStep); - m_deformableBodySolver->predictMotion(timeStep); -} - -void btDeformableMultiBodyDynamicsWorld::reinitialize(btScalar timeStep) -{ - m_internalTime += timeStep; - m_deformableBodySolver->setImplicit(m_implicit); - m_deformableBodySolver->setLineSearch(m_lineSearch); - m_deformableBodySolver->reinitialize(m_softBodies, timeStep); - btDispatcherInfo& dispatchInfo = btMultiBodyDynamicsWorld::getDispatchInfo(); - dispatchInfo.m_timeStep = timeStep; - dispatchInfo.m_stepCount = 0; - dispatchInfo.m_debugDraw = btMultiBodyDynamicsWorld::getDebugDrawer(); - btMultiBodyDynamicsWorld::getSolverInfo().m_timeStep = timeStep; - if (m_useProjection) - { - m_deformableBodySolver->m_useProjection = true; - m_deformableBodySolver->m_objective->m_projection.m_useStrainLimiting = true; - m_deformableBodySolver->m_objective->m_preconditioner = m_deformableBodySolver->m_objective->m_massPreconditioner; - } - else - { - m_deformableBodySolver->m_useProjection = false; - m_deformableBodySolver->m_objective->m_projection.m_useStrainLimiting = false; - m_deformableBodySolver->m_objective->m_preconditioner = m_deformableBodySolver->m_objective->m_KKTPreconditioner; - } -} - -void btDeformableMultiBodyDynamicsWorld::debugDrawWorld() -{ - btMultiBodyDynamicsWorld::debugDrawWorld(); - - for (int i = 0; i < getSoftBodyArray().size(); i++) - { - btSoftBody* psb = (btSoftBody*)getSoftBodyArray()[i]; - { - btSoftBodyHelpers::DrawFrame(psb, getDebugDrawer()); - btSoftBodyHelpers::Draw(psb, getDebugDrawer(), getDrawFlags()); - } - } -} - -void btDeformableMultiBodyDynamicsWorld::applyRigidBodyGravity(btScalar timeStep) -{ - // Gravity is applied in stepSimulation and then cleared here and then applied here and then cleared here again - // so that 1) gravity is applied to velocity before constraint solve and 2) gravity is applied in each substep - // when there are multiple substeps - btMultiBodyDynamicsWorld::applyGravity(); - // integrate rigid body gravity - for (int i = 0; i < m_nonStaticRigidBodies.size(); ++i) - { - btRigidBody* rb = m_nonStaticRigidBodies[i]; - rb->integrateVelocities(timeStep); - } - - // integrate multibody gravity - { - forwardKinematics(); - clearMultiBodyConstraintForces(); - { - for (int i = 0; i < this->m_multiBodies.size(); i++) - { - btMultiBody* bod = m_multiBodies[i]; - - bool isSleeping = false; - - if (bod->getBaseCollider() && bod->getBaseCollider()->getActivationState() == ISLAND_SLEEPING) - { - isSleeping = true; - } - for (int b = 0; b < bod->getNumLinks(); b++) - { - if (bod->getLink(b).m_collider && bod->getLink(b).m_collider->getActivationState() == ISLAND_SLEEPING) - isSleeping = true; - } - - if (!isSleeping) - { - m_scratch_r.resize(bod->getNumLinks() + 1); - m_scratch_v.resize(bod->getNumLinks() + 1); - m_scratch_m.resize(bod->getNumLinks() + 1); - bool isConstraintPass = false; - { - if (!bod->isUsingRK4Integration()) - { - bod->computeAccelerationsArticulatedBodyAlgorithmMultiDof(m_solverInfo.m_timeStep, - m_scratch_r, m_scratch_v, m_scratch_m, isConstraintPass, - getSolverInfo().m_jointFeedbackInWorldSpace, - getSolverInfo().m_jointFeedbackInJointFrame); - } - else - { - btAssert(" RK4Integration is not supported"); - } - } - } - } - } - } - clearGravity(); -} - -void btDeformableMultiBodyDynamicsWorld::clearGravity() -{ - BT_PROFILE("btMultiBody clearGravity"); - // clear rigid body gravity - for (int i = 0; i < m_nonStaticRigidBodies.size(); i++) - { - btRigidBody* body = m_nonStaticRigidBodies[i]; - if (body->isActive()) - { - body->clearGravity(); - } - } - // clear multibody gravity - for (int i = 0; i < this->m_multiBodies.size(); i++) - { - btMultiBody* bod = m_multiBodies[i]; - - bool isSleeping = false; - - if (bod->getBaseCollider() && bod->getBaseCollider()->getActivationState() == ISLAND_SLEEPING) - { - isSleeping = true; - } - for (int b = 0; b < bod->getNumLinks(); b++) - { - if (bod->getLink(b).m_collider && bod->getLink(b).m_collider->getActivationState() == ISLAND_SLEEPING) - isSleeping = true; - } - - if (!isSleeping) - { - bod->addBaseForce(-m_gravity * bod->getBaseMass()); - - for (int j = 0; j < bod->getNumLinks(); ++j) - { - bod->addLinkForce(j, -m_gravity * bod->getLinkMass(j)); - } - } - } -} - -void btDeformableMultiBodyDynamicsWorld::beforeSolverCallbacks(btScalar timeStep) -{ - if (0 != m_internalTickCallback) - { - (*m_internalTickCallback)(this, timeStep); - } - - if (0 != m_solverCallback) - { - (*m_solverCallback)(m_internalTime, this); - } -} - -void btDeformableMultiBodyDynamicsWorld::afterSolverCallbacks(btScalar timeStep) -{ - if (0 != m_solverCallback) - { - (*m_solverCallback)(m_internalTime, this); - } -} - -void btDeformableMultiBodyDynamicsWorld::addForce(btSoftBody* psb, btDeformableLagrangianForce* force) -{ - btAlignedObjectArray<btDeformableLagrangianForce*>& forces = m_deformableBodySolver->m_objective->m_lf; - bool added = false; - for (int i = 0; i < forces.size(); ++i) - { - if (forces[i]->getForceType() == force->getForceType()) - { - forces[i]->addSoftBody(psb); - added = true; - break; - } - } - if (!added) - { - force->addSoftBody(psb); - force->setIndices(m_deformableBodySolver->m_objective->getIndices()); - forces.push_back(force); - } -} - -void btDeformableMultiBodyDynamicsWorld::removeForce(btSoftBody* psb, btDeformableLagrangianForce* force) -{ - btAlignedObjectArray<btDeformableLagrangianForce*>& forces = m_deformableBodySolver->m_objective->m_lf; - int removed_index = -1; - for (int i = 0; i < forces.size(); ++i) - { - if (forces[i]->getForceType() == force->getForceType()) - { - forces[i]->removeSoftBody(psb); - if (forces[i]->m_softBodies.size() == 0) - removed_index = i; - break; - } - } - if (removed_index >= 0) - forces.removeAtIndex(removed_index); -} - -void btDeformableMultiBodyDynamicsWorld::removeSoftBodyForce(btSoftBody* psb) -{ - btAlignedObjectArray<btDeformableLagrangianForce*>& forces = m_deformableBodySolver->m_objective->m_lf; - for (int i = 0; i < forces.size(); ++i) - { - forces[i]->removeSoftBody(psb); - } -} - -void btDeformableMultiBodyDynamicsWorld::removeSoftBody(btSoftBody* body) -{ - removeSoftBodyForce(body); - m_softBodies.remove(body); - btCollisionWorld::removeCollisionObject(body); - // force a reinitialize so that node indices get updated. - m_deformableBodySolver->reinitialize(m_softBodies, btScalar(-1)); -} - -void btDeformableMultiBodyDynamicsWorld::removeCollisionObject(btCollisionObject* collisionObject) -{ - btSoftBody* body = btSoftBody::upcast(collisionObject); - if (body) - removeSoftBody(body); - else - btDiscreteDynamicsWorld::removeCollisionObject(collisionObject); -} - -int btDeformableMultiBodyDynamicsWorld::stepSimulation(btScalar timeStep, int maxSubSteps, btScalar fixedTimeStep) -{ - startProfiling(timeStep); - - int numSimulationSubSteps = 0; - - if (maxSubSteps) - { - //fixed timestep with interpolation - m_fixedTimeStep = fixedTimeStep; - m_localTime += timeStep; - if (m_localTime >= fixedTimeStep) - { - numSimulationSubSteps = int(m_localTime / fixedTimeStep); - m_localTime -= numSimulationSubSteps * fixedTimeStep; - } - } - else - { - //variable timestep - fixedTimeStep = timeStep; - m_localTime = m_latencyMotionStateInterpolation ? 0 : timeStep; - m_fixedTimeStep = 0; - if (btFuzzyZero(timeStep)) - { - numSimulationSubSteps = 0; - maxSubSteps = 0; - } - else - { - numSimulationSubSteps = 1; - maxSubSteps = 1; - } - } - - //process some debugging flags - if (getDebugDrawer()) - { - btIDebugDraw* debugDrawer = getDebugDrawer(); - gDisableDeactivation = (debugDrawer->getDebugMode() & btIDebugDraw::DBG_NoDeactivation) != 0; - } - if (numSimulationSubSteps) - { - //clamp the number of substeps, to prevent simulation grinding spiralling down to a halt - int clampedSimulationSteps = (numSimulationSubSteps > maxSubSteps) ? maxSubSteps : numSimulationSubSteps; - - saveKinematicState(fixedTimeStep * clampedSimulationSteps); - - for (int i = 0; i < clampedSimulationSteps; i++) - { - internalSingleStepSimulation(fixedTimeStep); - synchronizeMotionStates(); - } - } - else - { - synchronizeMotionStates(); - } - - clearForces(); - -#ifndef BT_NO_PROFILE - CProfileManager::Increment_Frame_Counter(); -#endif //BT_NO_PROFILE - - return numSimulationSubSteps; -} |